Well actually it's like if glIgnoreNearPlane was not taken into account, but sometimes the display is ok, only when I don't call the renderScene method, which happens here when "displayNeedsUpdate" is set to false :

If anything, I would have expected it to be the other way round. If you omit the renderScene()-call, the draw()-call actually triggers some additional calculations that had to be done per frame but are usually done in renderScene(). These calculations were done too early to take a modified plane into account. However, I'm not sure why this should explain the behaviour that you are describing.Anyway, I've updated the beta-jar of jPCT-AE. Please give it a try and see if that helps. If it doesn't (or makes things worse), can you please provide me with a test case?

Not necessarily. But from your description, it worked when you omit them but not if you are actually calling them...which puzzles me. Anyway, please give the modified jar a try and see if that helps. If not, try to move them out of this block and see if that helps. If that doesn't help either, I need a test case.

The new beta jar did not change anything, that said I have found the solution.Actually I use a skybox, and I was calling the skybox.render() method after world.renderScene().After switching this call order, everything works fine.